The government's chief legal adviser has insisted that the Iraq war was lawful.

The comments come despite Lord Butler finding that the intelligence reports used to justify the invasion were "seriously flawed".

Attorney general Lord Goldsmith's department said in a statement that UN security council resolutions justified the pre-emptive military action against Saddam Hussein.

"Lord Butler's review has seen the attorney general's advice. His report confirms - as we have always maintained - that it was 'based on the interpretation of relevant security council resolutions and negotiating history in the United Nations, and not on WMD-related intelligence'," said the statement.

It went on to say that the lawfulness of the conflict "is not undermined by the failure to find WMD or by any reassessment of the intelligence".

Added the statement: "The attorney's view is that the military action taken in Iraq was lawful. That was his independent view at the time, and it is still his view. The government has acted in accordance with the attorney's advice at all times."

The comments came as the Liberal Democrat leader Charles Kennedy repeated his demand for the publication of the full legal advice concerning the conflict.